Process and apparatus for tanning leather



June 30, 1931. R. CHAVAND 1,812,257

PROCESS AND APPARATUS FOR TANNING LEAThnR Filed Jan. 13. 1950 I yanfor Zena . process, the hides are suddenly stretched the fibers are abnormally stressed and the leather Patented June 30, 1931 UNITED STATES TE-Ni: oFi-"ica nmnt GHAYAND, or LYON,

raocnss nu) arramrus roa tmm- LEATHER Application filed January 18, 1930,8eria1 No. 20,586, and in. France Iannary 12, 1929.

My invention relates to a process of tanning leather for the manufacture of belts and to an' apparatus for carrying out said process. It has for its: object to produce belts 5 which do not grow longer at use whilst being highly elastic. l v

It has beenproposed to tan leather whilst under tension, the hides being tensioned, before tanning, on'suitable frames which are then immersed into the tanning bath. In this obtained is practically inelastic which is a most serious drawback in the belt industry.

tensioned progressively during. the-tanning operation.

The apparatus employed comprises. a stretching frame driven b a screw with roin such a way that'the hide begins to be tensioned when immersed in the tanning bath,

' the stetching being stopped when tanning is:

performed.

In the annexed drawings: g Fig.1 is asection on line II (Fig. 2). Fig. 2 is. a longitudinal section on hn'e 11-11 (Fig. 1).

The apparatus comprises two 1aws 1 and-2 to which the hide 3 is fixed by means of pins 4. Jaw 1 is pivotally fixed to a support 5; jaw 2 is also pivotably fixed to a U-shaped rod 6 which is fgided through support The latter is fixe ystays 7 to a vertical projection 7 integral 'Wltll the bottom of the tank 8 adapted to contain the tanning to drive rod 6. 0

This gear comprises a driving shaft 9 previded wlth a driving pulley 10. Shaft 9, is

provided with a worm 11 which meshes with- Wheel-15 is laterally maintained by the According to my invention, the hides are,

tating nut, and a-speed-re ucing set adjusted their elastic strength is low. The leather is bath. This tank also supports the reducing gear adapted which casing 17 of-the speed-reducing. gear. One- The operation is as follows: The hide is preferably cut into what wider than the belt to be 0 half of this casing is integral with tank 8.

ieces sometained and as long as possible. Such a piece isdisposed 66 on the pivotable jaws 1- and 2 and the gear is actuated so that a slight initial tension is given to the hide.

- The tanning bath 9 is then introduced into I tank 8 up to a-level somewhat above hide 3, .60

and pulley 10 is continuously rotated at such a speed that, when'the tanning operation is performed, the stretching. dangerously high. The bath is then removed I from the tank, the gear is rotated backwards until the piece of leather obtained is free and the latter is removed.

1 Owing to the progressive tension of the hide, the

the beginningof the tanning operation, when' wit such a leather do not substantially grow lefigcr at use while being elastically stretch- .a e.

I claim:

1. A process for the manufacture of leather for belts and the like, comprising the step of tanning a hide while progressively stretching it in one direction. j

2. A process for the manufacturei'ofleather for belts and the like, com risin the [step of tanning a piece of hide su' stantiall i be finally obtained as wide as the belt to while progressively stretching it in the direc- -tion o its length.

3. An a paratus continuous y stretching a piece of hide in one direction during the tanning operation, com-' prising a tank adapted to contain the tannin adaited to receive the ends .of the'piece of. .hide; means to clamp said ends on said jaws;

- a rectilinearly movable rod towhi'ch one of said jaws is pivotabl fixed; a'support'to which the other one o of the hide is not fibers are not suddenly stretched at v 9 for progresively and a bath; a pair ofjaws within said tank,

fixed; means to guide said rod; and means to ldrve said rod rectilinearly to tension said 4:. An apparatus. as claimed in claim 3 'Wherein the means to drive the rod comprise a threaded rod fixed at the end of said firstnamed rod; a rotatable nut on said threaded rod; means to laterally maintain said nut; and a speed-reducing gear adapted to drive said nut.

In testimony thereof I aflix my signature.

RENE GHAVAND. 

